It has been recently recognized that an arbitrary six-port junction, four arms of which are terminated in power meters, can be calibrated to measure the circuit parameters, v, i, z, a, b, Tau, etc., in addition to power. Because this scheme eliminates the need for frequency conversion, it provides a substantially simplified approach to the design of an automatic network analyzer. This paper outlines a calibration procedure for the six-port which is only slightly more complicated than that in use for existing automated measurement systems.